1. Field of the Invention
The present invention relates to a liquid jetting apparatus which jets liquid.
2. Description of the Related Art
As a liquid jetting apparatus which jets liquid, Japanese Patent Application Laid-open No. 2010-155417 describes a so-called serial type ink-jet printer. In the serial type ink-jet printer, an ink-jet head is carried on a carriage which moves in a scanning direction along guide rails (guide members) and printing is performed on a recording medium by jetting ink from the ink jet head which moves in the scanning direction together with the carriage.
In the ink jet printer as described in Japanese Patent Application Laid-open No. 2010-155417, four color inks supplied from four ink cartridges disposed outside the carriage are supplied to the ink jet head carried on the carriage, via tubes and a buffer tank carried on the carriage. The ink-jet head is disposed at one end portion in a direction perpendicular to the scanning direction of the carriage. Four storage sections (liquid storage tanks) storing the four color inks respectively are provided in the buffer tank at a portion positioned almost immediately above the ink jet head so that the four storage sections are aligned in a row in the upward and downward directions which is perpendicular to the scanning direction and the direction perpendicular to the scanning direction. Further, a wall of the upper or lower side of each of the four storage sections is formed of a film. In the buffer tank, it is also possible to suppress any pressure fluctuation of the ink contained in each storage section by deforming the film.
Further, in the ink-jet printer as described in Japanese Patent Application Laid-open No. 2010-155417, a driving belt extending in the scanning direction is installed to a front end portion of the carriage. The carriage is pulled by the driving belt to move in the scanning direction.
Here, in the ink-jet printer as described in Japanese Patent Application Laid-open No. 2010-155417, the front end portion of the carriage to which the driving belt is installed is pulled by the driving mechanism to move the carriage in the scanning direction. On the other hand, the ink-jet head which is heavy in weight and the storage sections which are heavy in weight at the time of storing the inks are arranged in the carriage at the other end portion disposed on the side opposite, in the direction perpendicular to the scanning direction, to the one end portion to which the driving belt is installed. Therefore, the center of gravity of the carriage is positioned at a position separated from the one end portion to which the driving belt is installed. Accordingly, the moment, which is applied to the carriage by force generated when the driving belt pulls the carriage to move the carriage in the scanning direction, is increased.
In the ink-jet printer as described in Japanese Patent Application Laid-open No 2010-155417, any backlash is commonly provided between the carriage and the guide rails so that the carriage can move smoothly. Thus, when the moment applied to the carriage is increased, the carriage wobbles (oscillates) during the movement. As a result, there is fear that a position of landing (landing position) of the ink is deviated, thereby deteriorating printing quality.
In recent years, in the ink-jet printer as described in Japanese Patent Application Laid-open No. 2010-155417 etc., there is a tendency of increasing the number of nozzles for the purpose of, for example, speed-up of the printing and/or improvement of the printing quality. If the number of the nozzles is increased, the ink-jet head becomes large in proportion to the number of the nozzles, Corresponding to this, the storage sections also become large in order to supply the inks to the ink-jet head sufficiently. As a result, the center of gravity of the carriage is positioned at a position farther separated from the one end portion to which the driving belt is installed, and thereby further increasing the wobbling (oscillating) of the carriage as described above.
An object of the present teaching is to provide a liquid jetting apparatus which is capable of suppressing wobbling (oscillating) of the carriage during movement.